<template>
  <div :class="classes">
    <slot></slot>
  </div>
</template>
<script>
import { findComponentsDownward, oneOf } from '../../utils/assist';
import Emitter from '../../mixins/emitter';

const prefixCls = 'ivu-checkbox-group';

export default {
  name: 'CheckboxGroup',
  mixins: [Emitter],
  props: {
    value: {
      type: Array,
      default() {
        return [];
      }
    },
    size: {
      validator(value) {
        return oneOf(value, ['small', 'large', 'default']);
      },
      default() {
        return !this.$IVIEW || this.$IVIEW.size === '' ? 'default' : this.$IVIEW.size;
      }
    }
  },
  data() {
    return {
      currentValue: this.value,
      childrens: []
    };
  },
  computed: {
    classes() {
      return [
        `${prefixCls}`,
        {
          [`ivu-checkbox-${this.size}`]: !!this.size
        }
      ];
    }
  },
  mounted() {
    this.updateModel(true);
  },
  methods: {
    updateModel(update) {
      this.childrens = findComponentsDownward(this, 'Checkbox');
      if (this.childrens) {
        const { value } = this;
        this.childrens.forEach(child => {
          child.model = value;

          if (update) {
            child.currentValue = value.indexOf(child.label) >= 0;
            child.group = true;
          }
        });
      }
    },
    change(data) {
      this.currentValue = data;
      this.$emit('input', data);
      this.$emit('on-change', data);
      this.dispatch('FormItem', 'on-form-change', data);
    }
  },
  watch: {
    value() {
      this.updateModel(true);
    }
  }
};
</script>
